When "abegg" is read and ("A, B, E, G, G") is not: a cortical stimulation study of musical score reading

To spare the cortical areas involved both in musical score reading and in language, the authors used a score reading task during direct cortical stimulation mapping in musicians undergoing operations for brain lesions. The organization of the cortical areas involved in language and score reading, respectively, was analyzed in relation with these surgical data.

Seven patients with brain lesions were tested using three language tasks and a score-reading task. Preoperatively, none of them had exhibited significant language or musical ability deficits, and all had a special interest in music. All were involved in professional or amateur musical activities. Interference in score reading was found in small cortical areas, mainly in the dominant parietal lobe and sometimes in the frontal gyri. During direct stimulation, interference was either language-specific (15 sites), common to language and score-reading tasks (18 sites), or specific to the score-reading task (four sites). Different patterns of score-reading interferences (score-reading arrest, semantic paraphasia) were observed, probably corresponding to different stages of score reading. Postoperatively, some patients showed transitory score-reading difficulties related to the surgical procedure.

The cortical areas involved in score reading can occasionally be distinct from other language areas. This could explain differential word- and score-reading impairments sometimes observed in musicians with brain lesions. Brain mapping for neurosurgical procedures in musicians should ideally be performed using a score-reading task in addition to standard language tasks, especially for mapping in the dominant parietal lobe.